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Should I use scipy.pi, numpy.pi, or math.pi?
...gt;> math.pi == np.pi == scipy.pi
True
So it doesn't matter, they are all the same value.
The only reason all three modules provide a pi value is so if you are using just one of the three modules, you can conveniently have access to pi without having to import another module. They're not provi...
Make Div overlay ENTIRE page (not just viewport)?
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The viewport is all that matters, but you likely want the entire website to stay darkened even while scrolling. For this, you want to use position:fixed instead of position:absolute. Fixed will keep the element static on the screen as you sc...
Update a record without first querying?
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@Gabriel Won't this update all properties though? What if I only want to modify a single one?
– David Pfeffer
Aug 15 '12 at 0:45
22
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What is the difference between a .xib file and a .storyboard?
...ated .xib with it. Storyboard achieves two things:
.storyboard is essentially one single file for all your screens in the app and it shows the flow of the screens. You can add segues/transitions between screens, this way. So, this minimizes the boilerplate code required to manage multiple screens....
DLL and LIB files - what and why?
...program to run properly - libraries. But why do compilers generate them at all? Wouldn't it be easier to just include all the code in a single executable? And what's the difference between DLL's and LIB's?
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All Ruby tests raising: undefined method `authenticate' for nil:NilClass
Most of my tests are raising the following and I don't understand why. All methods call raise the 'authenticate' error. I've checked the code if there was a method called "authenticate" but there is no such method.
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Can you have if-then-else logic in SQL? [duplicate]
...SE statement is the closest to an IF statement in SQL, and is supported on all versions of SQL Server:
SELECT CASE <variable>
WHEN <value> THEN <returnvalue>
WHEN <othervalue> THEN <returnthis>
ELSE <returndefaultcase>
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ASP.NET: This method cannot be called during the application's pre-start initialization stage
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I see. It automatically defines security and membership rules so you have to override them before you add custom ones. Tricky.
– Jonathan Allen
May 25 '11 at 8:46
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Linux/Unix command to determine if process is running?
...s arg vector. Any such approach is doomed to fail sooner or later (you actually admit to that yourself, by saying that more checks are needed). I've added my own recommendation in a separate answer.
– peterh
Oct 3 '13 at 10:41
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What's the fastest way to loop through an array in JavaScript?
...o
Currently, the fastest form of loop (and in my opinion the most syntactically obvious).
A standard for-loop with length caching
var i = 0, len = myArray.length;
while (i < len) {
// your code
i++
}
I would say, this is definitely a case where I applaud JavaScript en...